Chapter 4 Building Conceptual Data Models
You can double-click any inheritance symbol in the diagram to display its properties:
Property | Description |
---|---|
Name | The name of the item which should be clear and meaningful, and should convey the item's purpose to non-technical users |
Code | The technical name of the item used for generating code or scripts, which may be abbreviated, and should not generally include spaces |
Comment | Descriptive label for the inheritance link |
Stereotype | Sub-classification used to extend the semantics of an object without changing its structure; it can be predefined or user-defined |
Parent | Name of the parent entity |
Mutually exclusive children | Indicates if only one child can exist for one occurrence of the parent entity. |
Complete | Indicates that all instances of the parent entity (surtype) must belong to one of the children (subtypes). For example, entity Person has 2 sub-types Male and Female; each instance of entity Person is either a male or a female |
An inheritance link definition also includes the following properties, which are defined on associated property sheets:
Property | Description |
---|---|
Generation | Group of properties that affect physical implementation |
Children | List of child entities |
Notes | Description associated with inheritance link |
Rules | Business rules attached to the inheritance link |
Depending on the model notation, the inheritance symbol displays the inheritance status:
IDEF1X | E/R and Merise notation | Description |
---|---|---|
Standard | ||
— | Mutually exclusive inheritance | |
Complete inheritance | ||
— | Mutually exclusive and complete inheritance |
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